Ground Report | New Delhi: Agricultural yield will plummet; Climate-related impacts on crop yields are a relevant concern for international organizations, such as the Food and Agriculture Organization of the United Nations (FAO), which believes that the climate crisis, without due adaptation, could take us even further away from the second Sustainable Development Goal (SDG 2) related to hunger.
Agricultural yield will plummet
In this sense, NASA has published a new study in which it updates the projections of crop yields made in the near past with the advances of new technologies to show precisely how the production of corn, soybeans, and soy will increase or decrease.
In the text, published in the journal Nature, they have pointed out that, due to the increase in temperature, the changes in the rainfall patterns, and the high concentrations of carbon dioxide that will exist in the most pessimistic scenarios, the yield of the crops of Corn by 2030 will decline 24%, while wheat could see an increase of around 17%.
“We did not expect to see such a substantial change compared to projections based on the old models. The projected response from maize was surprisingly large and negative as a 20% decline from current production levels could have serious implications on a global scale, ”said Jonas Jägermeyr, one of the study’s authors.
To obtain their projections, the team of researchers used two sets of models. First, they used simulations from the last phase of the Coupled Model Intercomparison Project (CIMP). They then introduced 12 state-of-the-art global crop models that are part of the Agricultural Models Intercomparison and Improvement Project (AgMIP).
impacts of climate change
According to NASA, these latest models simulate on a large scale how crops grow and respond to different environmental conditions such as temperature, rainfall, and atmospheric carbon dioxide, based on real biological responses studied in the laboratory and outdoors.
At the end of the process, the team created around 240 global climate model simulations for each type of crop in order to observe their development over the years and decades in each part of the world and under the impacts of climate change.
In this way, they observed that the projections for soybeans and rice showed a decrease in some regions, but on a global scale the different models still did not agree on the general impacts of climate change. For corn and wheat, the climate effect was much clearer, and most of the model results pointed in the same direction.
Wheat, which grows best in temperate climates, may have a wider growing area as temperatures rise, including the northern United States and Canada, the northern plains of China, Central Asia, southern Australia, and East Africa. But these gains could stabilize by mid-century.
Temperature is not the only factor that models take into account when simulating future crop yields. Higher levels of carbon dioxide in the atmosphere have a positive effect on photosynthesis and water retention, increasing crop yields, although this often makes them less nutritious. This effect is seen to a greater extent in wheat than in corn.
Rising global temperatures are also related to changes in rainfall patterns and the frequency and duration of heatwaves and droughts, which can affect crop health and productivity. Higher temperatures also affect the length of growing seasons and accelerate crop maturity.
“You can think of plants harvesting sunlight over the course of the growing season. They get that energy and put it in the plant and in the grain. So if their growth stages are accelerated, by the end of the season they just haven’t collected as much energy. As a result, the plant produces fewer grains than it would with a longer development period and, therefore, as it grows faster, its yield decreases ”, explained Alex Ruane, co-author of the study.